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its being shunted which means its receiving current just not 120v of current correct each other load is receiving right?
Let’s make sure you are keeping current and voltage straight.
Current (in “amps”) is electrons flowing through a closed circuit.
Voltage (in “volts”) is the pressure, or charge, that gives the electrons the push to want to move in the circuit. You can have a lot of potential voltage, but if there isn’t a complete circuit, current won’t flow.
Voltage drop is a measurable voltage that is created by current flowing through a load.
In these circuits, with the detector switch closed, the main coil is shunted. If there is a path available to electrons with no resistance (no load), they will take that path 100% of the time. That is a shunt. This is what is happening here. And it results in the booster and the ignitor simply being in parallel with each other, and not in series with anything. This is why we can know the voltage drops for all of the loads in this scenario without having to actually calculate them.
By the way, when that detector switch is open, then the main coil is in series with both the ignitor and the booster, and you’d have a series-parallel situation.
Take one more look at the circuits and think it through one more time to make sure you really get it. Being able to see what is going on in a basic schematic is CRITICAL for good troubleshooting.
since the main coil is shunted off the answer for the mail coil will be 0v correct?
Correct
Correct!
So, what do you think is happening with the main coil. Is it receiving any current, or is it being shunted?
Correct.
Then why would any current ever go through the main coil when the detector switch is closed?
There’s a special circumstance that we talked about in Unit 5 that can cause a load to not receive any current. What is that called?
We were posting at the same time. So let me repeat a little:
You said in one of your responses that the Booster has direct access to L1 and N (through the detector switch).
Does the ignitor have the same situation?
In order for loads to be in series, there cannot be any alternate path that electrons can take. Is that the case with the booster and the main, based on what you just said above?
Oops – my “yes” was to your first response
Yes! And does the same thing happen if you are the ignitor? And if so, why would any current flow through the main coil?
Okay – that is where your mistake is.
There is something you aren’t seeing that affects one of the loads.
Try doing the Zen trick on the Booster. Become the booster. Imagine you are reaching out for L1 and N with your hands. Can you get there directly or do you have to go through any other loads?
No- please answer the question I asked. If you don’t know the answer, just say so. I’m trying to step you through the thought process you need to go through to get to the correct answers
It is given clearly in unit 5. The rule of thumb, which is perhaps more important to know, is also shown on the third video. We also asked you a quiz question about it. Please look at that section of Unit 5, and let me know if something isn’t clear to you
Voltage drop occurs when current flows though a load.
The first question you need to ask yourself is: Do all 4 loads have current flowing through them, as the circuits are shown in the diagram? (With the detector switch closed) Please just answer that question for me
Hi Philip,
Yes, that is correct!
That is not correct, which is why I asked how you arrived at it. If I know what your thinking is, then I can see where your mistake is and help you better.
Do you think that the main coil is in series with some of the other loads? If so, then it would have to share the voltage drop with them. That would mean any loads it was in series with would not be able to drop 120vac.
Normally, to calculate voltage drop across loads in series, you would need to know the resistance of each load. Like you did in Question 4 on the midterm. But we don’t give you any resistances for Question 8, and we still say that you can give us a numerical answer for each voltage drop.
The key is accurately seeing the layout of the loads, given the state of the circuits as shown in the diagram.
A first question to ask yourself is: Do all of the loads receive current?
Let me know what you think.
and the booster is 30v
You mentioned the booster twice. Did you mean to say the main coil here?
What is your explanation for the 30vac?
By the way, if you watch that video I asked you to, he addresses the danger of thinking about “the path of least resistance.”
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